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ABSTRACT- 1) A NANB agent of human origin was inoculated in HBV-immunized chimpanzees. Infection was proven in two animals and serially passed to two others. The absence of anti-HBc in serum and the absence of HBsAg and HbcAg in liver are arguments against the HBV nature of the transmitted infection. Moreover, the reproducible appearance of the NANBcAg/Ab system at each passage from man to chimpanzee and from chimpanzee to chimpanzee, a response not elicited in control animals, suggests that this reaction may be a specific immunologic marker for the strain. 2) NANB infection was transmitted in all chimpanzees. 3) Distinctive hepatic morphologic features were obtained in the liver biopsies of the human donor and the inoculated chimpanzees: eosinophilic alterations of hepatocytes and numerous inflammatory cells. Inflammation was more prominent than necrosis, appearing earlier and lasting longer, but was not topographically close to the eosinophilic changes. 4) On electron microscopy, particles characteristic of NANB agent were observed in the cytoplasm of the hepatocytes. No particles were demonstrated in the nucleus of these cells. [ABSTRACT FROM AUTHOR]

Ulcer recurrence is probably related to residual Helicobacter pylori (H pylori). Histological examination and culture are considered to be the most specific tests. CLO test is a rapid but less specific test, which is usually used as an alternative test to culture. The aim of this study was to investigate the efficiency of a simplified polymerase chain reaction (PCR) assay as a procedure for the diagnosis of gastric H pylori infection of patients. Biopsy specimens were obtained from antral mucosa of 58 patients at endoscopy and submitted to four tests for detection of H pylori. The bacteria were found in 53%, 43%, 48%, and 50% of patients according to the results of PCR, CLO test, culture, and histological examination. Twenty three patients had both negative histology and negative culture and PCR was negative in all of these. Thirteen patients were not classified because only histology or culture was positive and 10 of these had a positive PCR test. When the diagnosis of H pylori was established by agreement with both histology and culture or three positive tests out of four, 29 patients were H pylori positive (28 having had three positive tests and one displaying positive histology and culture), and 26 were negative, and three undetermined. PCR proved the most sensitive and specific test. These results suggest the simplified PCR assay may be a valuable test for the detection of H pylori. [ABSTRACT FROM PUBLISHER]

Ten patients in whom cystic dystrophy developed in a heterotopic pancreas of the duodenal (nine patients) or gastric (one patient) wall are reported. All were young or middle aged white men, only two of whom were alcoholic. The symptoms were caused by intestinal or biliary stenosis, or both, secondary to the inflammation and fibrosis. Only endosonography provided strong evidence for the diagnosis in three patients. All patients underwent surgery: a pancreaticoduodenectomy was performed in eight patients. The surgical specimen showed cystic lesions of the gut wall, occurring in inflammatory and fibrous heterotopic pancreatic tissue. The pancreas proper was normal in all patients. It is suggested that cystic dystrophy is an uncommon and serious complication of heterotopic pancreas. Similar cases associated with chronic pancreatitis of the pancreas have been observed and it is suggested that this process could be responsible for some of the chronic pancreatitis encountered in young, non-alcoholic patients. [ABSTRACT FROM PUBLISHER]

The present study shows that the distribution of T lymphocytes in gastrointestinal carcinomas and their metastases mimic the distribution of T lymphocytes in normal intestine. The composition of the peritumoral reaction resembled that of normal lamina propria with a predominance of CD3 + CD4 + T cells. In contrast, lymphocytes located between carcinomatous cells showed phenotypical features similar to those of intraepithelial lymphocytes (IEL) in normal intestine; in particu(abstractlar they expressed the antigen defined by HML-1, a monoclonal antibody raised against normal human intestinal IEL which reveals 95% IEL but very few cells in lymphoid (abstractorgans and blood. As normal intestinal IEL, the majority of intratumoral lymphocytes had the CD3+ CD8+ phenotype. A panel of monoclonal antibodies and double immunostaining techniques permitted a better characterisation of minor subsets of IEL. Two subsets of HML1 + CD3 + CD4- CD8- and of HML1+ CD3- cells, representing 2% and 3% of normal intestinal IEL respectively, did not significantly increase in carcinomatous epithelium. In contrast, in carcinomatous epithelium, but not in normal intestinal epithelium, we observed the appearance of a few lymphocytes displaying the phenotype of activated T cells (CD25+) or of natural killer cells (NKHI+) or of suppressor cells (CD11+). Such cells may participate in antitumoral defence. Although a similar population of HML1+ lymphocytes is associated with normal and carcinomatous intestinal epithelium, some interactions between lymphocytes and epithelial cells may not be maintained in tumoral epithelium. It has previously been shown that HLA-DR expression by enterocytes is modulated by intraepithelial lymphocytes. In our study, no correlation could be shown between the degree of lymphocytic infiltration and the expression of HLA-DR antigens on carcinomatous cells. [ABSTRACT FROM PUBLISHER]

A joint prospective long term study of gastric biopsies has been undertaken to survey intestinal metaplasia Types I, II, and III in terms of their incidence, distribution and value in the selection of high risk cancer patients. This study is based on protocols agreed between three centres for endoscopy, histological interpretation, and mucin histochemistry. The results on the first 1350 gastric biopsies examined during 1981-1982 are presented. Intestinal metaplasia was found in 267 biopsies (20%), being common in association with carcinoma (71%), less so in benign conditions such as gastric ulcer (39%), and chronic gastritis (24%), but rare in 'normal' (3%). Type I intestinal metaplasia was predominant (73%) in all the biopsies with intestinal metaplasia and was most common in benign conditions, 70% in gastric ulcer and 76% in chronic gastritis. Type III intestinal metaplasia (incomplete sulphomucin-secreting intestinal metaplasia) was recorded in only 9.8% of all the biopsies with intestinal metaplasia and had a higher incidence in carcinoma (35%), than in benign conditions (7%) (p less than 0.0001). These results suggest that intestinal metaplasia types may have different malignant potential and their identification may be useful in screening patients for early detection of cancer. [ABSTRACT FROM PUBLISHER]

Peliosis hepatis, an uncommon liver lesion characterised by blood-filled cavities bordered by hepatocytic plates, was found in 12 patients three to 17 months after renal transplantation. Hepatomegaly and portal hypertension were present in five of the six patients with major peliosis hepatis, and were absent in the other six with minor hepatic lesions. Alterations of centrilobular vein walls in some of these patients suggest that peliosis hepatis could be the result of a blockade or liver blood outflow at the junctions of sinusoids and centrilobular veins. The cause of these alterations might be azathioprine. [ABSTRACT FROM PUBLISHER]

AIMS--To establish the prevalence of c-erbB-2 protein expression in a surgical series of Barrett's adenocarcinomas; and to correlate this expression with clinicopathological data and prognosis. METHODS--Sixty six surgical specimens of Barrett's adenocarcinomas were included in this retrospective study. Blocks of the tumour and of non-dysplastic Barrett's mucosa were stained with a polyclonal antibody specific for the intracytoplasmic domain of the c-erbB-2 protein. RESULTS--Seven of 66 tumours showed membrane staining for the c-erbB-2 protein. The non-dysplastic Barrett's mucosa was negative in all cases. There was no difference between c-erbB-2 positive and negative tumours with regard to mean age, sex ratio, percentage of alcohol misusers, percentage of smokers, tumour differentiation, depth of invasion, lymph node response, and proliferative activity, assessed by the percentage of tumour cells positive with the MIB-1 antibody directed against the Ki-67 antigen. All c-erb B2 positive tumours were of Lauren's intestinal type compared with negative c-erbB-2 tumours. Patients with c-erbB-2 positive tumours had a significantly poorer prognosis than patients with negative tumours. CONCLUSIONS--The prevalence of Barrett's adenocarcinomas expressing c-erbB-2 found in this study (11%) was similar to that observed in published series of gastric adenocarcinomas. c-erbB-2 protein expression could be an important prognostic indicator in Barrett's adenocarcinoma. [ABSTRACT FROM PUBLISHER]

AIMS--To study the overexpression of p53 protein in Barrett's oesophagus with adenocarcinoma, and to correlate this expression with the pathological features of Barrett's syndrome. METHODS--Immunohistochemical staining was performed on frozen sections with a monoclonal antibody directed against wild type and mutated p53 protein (Pab 1801). Eleven cases of Barrett's adenocarcinoma were studied, seven of which had extensive sampling of benign Barrett's mucosa. RESULTS--Eight of 11 adenocarcinomas overexpressed the p53 protein. Both early and advanced tumours were positive. In Barrett's mucosa around the p53 positive tumours, high grade dysplasia was positive; low grade dysplasia and non-dysplastic mucosa were negative. CONCLUSIONS--P53 gene mutation with ensuing p53 protein overexpression is a common feature of Barrett's adenocarcinoma, both at early and advanced stages. This mutation appears as a relatively late event during the neoplastic transformation of Barrett's oesophagus. [ABSTRACT FROM PUBLISHER]

The lymphoid stromal reaction, particularly the T lymphoid reaction, was studied immunohistochemically on cryostat sections in 14 cases of primary gastrointestinal B lymphomas, and compared with the type and distribution of lymphoid cells in three cases of gastric lymphoid hyperplasia. A pronounced T lymphoid reaction, mainly of the T helper phenotype, occurred in both lesions. Most of these T cells bore HLA-DR antigens, but only a few of them had the receptor for interleukin 2. The T lymphoid reaction was observed inside the lymphomas in seven of a total of 14 cases, and around the lymphomas in four of the six cases clinically classified as stage I. Perivascular mucosal and submucosal nodules, entirely composed of T cells, seemed characteristic of gastric lymphoid hyperplasias. A T lymphoid reaction in lymphoid hyperplasias suggests an amplification of the cell mediated immune response; in lymphomas it could represent a host reaction against the lymphomatous infiltrate, therefore favouring a better prognosis. [ABSTRACT FROM PUBLISHER]

Columnar epithelium-lined oesophagus (CELO) is an acquired disorder associated with a high incidence of cancer. CELO consists of three histological types of epithelium: gastric-fundic, junctional, and specialised columnar, the last resembling intestinal metaplasia of the stomach. In a previous study of CELO an incompletely differentiated variant of intestinal metaplasia secreting sulphomucins (type II B) was found. This was shown to be associated with well differentiated adenocarcinoma, as in the stomach. The purpose of this paper has been to define by histochemistry the mucin profile of CELO in 17 patients and to compare it with the mucin profile of the gastroesophageal junction in 27 patients without CELO. In CELO a specialised columnar epithelium was always found and type II B intestinal metaplasia (with sulphomucins) showed the highest incidence (53%). In normal subjects, this type of intestinal metaplasia was found in only three of 27 cases. Type II B intestinal metaplasia has often been considered as a precancerous lesion or as an equivalent of dysplasia; consequently, its high incidence in our study on CELO raises the question of whether this lesion should be considered a high risk condition for adenocarcinoma of the lower oesophagus. [ABSTRACT FROM PUBLISHER]

Four hundred and thirty-three patients with adenomatous polyps were examined and followed up. It was found that well differentiated adenomas are stable but dedifferentiated polyps can lead to invasive cancer, usually over a long period of time. Thus the concept of malignant transformation becomes meaningless, and should be replaced by an initial histological evaluation of polyps of the rectum and colon so that their development can be predicted. [ABSTRACT FROM PUBLISHER]

Lymphocytic gastritis is a form of gastric inflammation characterised by a pronounced increase in lymphocytes in gastric surface and foveolar epithelium. Lymphocytic gastritis is often associated with endoscopic evidence of 'varioliform gastritis'. Lymphocytic gastritis has recently been reported to be associated with other forms of hypertrophic gastropathies. We present a case of hypertrophic gastropathy with gastric adenocarcinoma, with both Menetrier's disease and lymphocyte gastritis. Immunohistochemical studies showed that the intraepithelial lymphocytes were predominantly alpha/beta T cells as in the normal stomach and not gamma/delta T cells as in coeliac sprue. This case together with the six recently published cases suggests that Menetrier's disease and lymphocytic gastritis may be part of the same disease spectrum. [ABSTRACT FROM PUBLISHER]

Abstract: The cardiac sodium channel (SCN5A, NaV1.5) is a key determinant of electrical impulse conduction in cardiac tissue. Acute myocardial infarction leads to diminished sodium channel availability, both because of decreased channel expression and because of greater inactivation of channels already present. Myocardial infarction leads to significant increases in reactive oxygen species and their downstream effectors including lipoxidation products. The effects of reactive oxygen species on NaV1.5 function in whole hearts can be modeled in cultured myocytes, where oxidants shift the availability curve of I Na to hyperpolarized potentials, decreasing cardiac sodium current at the normal activation threshold. We recently examined potential mediators of the oxidant-induced inactivation and found that one specific lipoxidation product, the isoketals, recapitulated the effects of oxidant on sodium currents. Isoketals are highly reactive γ-ketoaldehydes formed by the peroxidation of arachidonic acid that covalently modify the lysine residues of proteins. We now confirm that exposure to oxidants induces lipoxidative modification of NaV1.5 and that the selective isoketal scavengers block voltage-dependent changes in sodium current by the oxidant tert-butylhydroperoxide, both in cells heterologously expressing NaV1.5 and in a mouse cardiac myocyte cell line (HL-1). Thus, inhibition of this lipoxidative modification pathway is sufficient to protect the sodium channel from oxidant induced inactivation and suggests the potential use of isoketal scavengers as novel therapeutics to prevent arrhythmogenesis during myocardial infarction. [Copyright &y& Elsevier]